Apack is a
Korean manufacturer of thermal solutions whose main product
lines focus on heat pipe technology, vapor chambers and micro electro
mechanical systems (MEMS). This is the first time FrostyTech has looked
into Apack's
consumer-grade heatsinks, but it's evident that the company has been heavily involved in
the OEM industry for the past several years; both in notebook thermal
solutions and high density server processor cooling.

The Apack
Zerotherm BTF90 and BTF80 heatsinks are the companies' first consumer class heatsinks for the AM2 platform,
and in spite of the kitschy 'butterfly' shaped cooling fins the BTF90 is
surprisingly effective. The 678 gram Zerotherm BTF90 is an all copper
heatsink which is designed to function with socket 775 Intel Pentium D/Core 2 Duo,
and socket 754/939/940/AM2 AMD Athlon64 processors. Socket 478 CPUs are not
supported. The cooler is rated for loads of up to
150W.

The
heatsinks' 92mm PWM fan is internally illuminated with a pair of
red LEDs that bounces off the translucent blades in a pleasing manner. The Zerotherm
BTF90 heatsink stands nearly 125mm high, but is only
slightly wider than the socket AM2/939 retention frame. The fan spins at 2500RPM and
includes Pulse Width Modulation (4-pin PWM) speed control, a
feature that is being adopted by motherboard manufacturers for both Intel and AMD
platforms. Fan noise is moderate at most, so the Zerotherm BTF90 is fairly unobtrusive
under power.

RoHS compliance is noted on the side of the packaging, a
crucial change for all consumer electronics since the July 1st implementation of this
European mandate came into effect. A set of four 6mm copper
sintered heatpipes twist their way through the stack of cooling fins, and connect
the copper base to the rest of the unit. Solder is used to bond the
heatpipes to the base section, so we can only assume a lead-free
solder has been used.

One Clip, Four K8 Processor Sockets

The Apack Zerotherm BTF90 heatsink comes with two sets of
clips for attaching to either socket 775 or socket 754/939/940/AM2 processors. Depending on the specific computer architecture, one clip or the
other is attached to the die-cast aluminum base of the BTF90 heatsink with
four screws before it can be used.

The socket 775 clip uses four spring tensioned captive
screws and a motherboard support bracket that requires users to remove the motherboard from
the computer before installation. An adhesive on the support bracket holds it in
place once installed behind the 775-pin socket.

The AMD heatsink bracket will work with both socket AM2
and socket 754/939/940 retention frames, it uses the center tab to clip in
place. The clip is a bit stiff to disengage, but installs in a
snap. The plus side to both clips is they can be oriented in any
direction, allowing users to install the Apack Zerotherm BTF90 heatsink so warm air is exhausted
towards the rear of the computer chassis.

FrostyTech's K8 Test Methodology is outlined in detail
here if you care to know what equipment is used, and the parameters under
which the tests are conducted. Now let's move forward and take a closer look at
this heatsink, its acoustic characteristics, and of course it performance in the
thermal tests!